Infertility has been recognized as a public health issue worldwide by the World Health Organization (WHO) (Boivin J et al 2007, Human Reproduction Vol. 22: 1506-1512). Infertility is defined as 12 months of frequent, unprotected intercourse during which pregnancy has not occurred. An estimated 10% to 15% of couples in the United States are infertile (Jose-Miller and Boyden, 2007). The problem occurs worldwide (Aitken et al., 2006; Ashkani et al., 2006; Bayasgalan et al., 2004; DSouza et al., 2004; Jensen et al., 2005; Mehta et al., 2006; Qadan et al., 2007; Sallmen et al., 2003; Sharp 2000; Sokol et al., 2006; Su et al., 2006; Swai et al., 2006; Swan et al., 2003; Thonneau et al., 1991 and Toppari et al., 2002), with increasing rate over the last decades (Aitken 2006). One of the reasons is a drop in testosterone concentrations of about 1.2% per year, or about 17% overall between 1987 and 2004 (Travison et al, 2007). In about 30% of cases the two partners are jointly responsible for childlessness. In an additional 60% of cases, each partner is the sole cause of infertility (30% each). In 10% no explanation can be found, and the sterility is called “idiopathic” or “unexplained infertility” (Crazzolara et al., 2007).
Today, semen assessment and sperm cells enrichment are done only in private or public male fertility laboratories, not accessible to patients due to the need of qualified technicians and equipment.
Human spermatozoa display marked heterogeneity, and therefore a variety of sperm abnormalities can be found in semen samples—even in those of fertile men (Nallella et al., 2006). To date, no single laboratory test can assess a man's total fertility (Evenson, 1999). A combination of sperm characteristics, such as semen volume (Nallella et al., 2006), sperm count, and percentage of motile (Nallella et al., 2006; Guzick et al., 2001) and normal forms (Nallella et al., 2006; Guzick et al., 2001; Bartoov et al., 2002), considered in correct proportions, provides the best diagnostic profile that could distinguish between fertile and suspected infertile male groups (Nallella et al., 2006; Guzick et al., 2001). Other parameters, such as white blood cell concentration in the semen, can also affect sperm function (Wolff, 1995).
IUI is one of the most frequently used fertility treatments for sub-fertile couples (The ESHRE Capri workshop group, 2009; Bensdrop et al., 2007). It is widely accepted that sperm motility, and the percentages of progressively motile sperm cells and of spermatozoa with normal morphology are the best predictors of pregnancy by IUI (Boomsma et al., 2007; Keck et al., 1997). To this end, various semen preparation techniques have been developed to separate the motile, morphologically normal spermatozoa (Allamaneni et al., 2005) from the rest. The classical swim-up method was developed by Mahadevan & Baker (Mahadevan and Baker, 1984). More complicated techniques were introduced later (Allamaneni et al., 2005). All these techniques are based on cell migration, density gradient centrifugation, and filtration. Movement of the spermatozoa is an essential prerequisite for the migration and swim upmethods, whereas the density gradient centrifugation and filtration techniques are based on a combination of sperm cell motility and their retention at phase borders and adherence to filtration matrices (Henkel and Schill, 2003).
The ideal sperm separation and/or preparation technique should (a) be quick, easy, and cost-effective, (b) isolate as many motile spermatozoa as possible, (c) not cause sperm damage or any physiological alterations of the separated sperm cells, (d) eliminate dead spermatozoa and other cells, including leukocytes and bacteria, and (e) allow the processing of larger volumes of ejaculates (Henkel and Schill, 2003).
Currently there are numerous number of techniques for sperm cells separation:                Sperm wash. said technique is a simple centrifugation wash and subsequent re-suspension of the male sperm cells.        Cost: Relatively high per procedure (disposables and medium per semen sample of 3 ml)        Disadvantages: such procedure is most likely not removing the deadspermatozoa and other cellular elements of semen (leukocytes, epithelial cells, anucleate cytoplasmic bodies, particulate debris, immature sperm cells and immotile sperm cells). Centrifugal pelleting of unselected sperm populations from human ejaculates causes the production of reactive oxygen species, that inducing irreversible damage to the spermatozoa and impairment of their fertilization ability (Mortimer, 1994). Centrifugation is needed.        Swim-up procedure: such procedure is based on the active movement of spermatozoa from the centrifuged prewashed cell pellet or directly from the liquefied semen into an overlaying medium during 60 minutes. Swimming sperm cells are selected. The procedure requires: Centrifuge (an optional), incubator, a 15 ml cone tube, 1.2 ml of sperm medium. Extra medium is needed if centrifugation is done or multiple tubes are used.        Costs: Relatively high costs per procedure (disposables and medium per semen sample of 3 ml, without and with pre-wash, respectively).        Disadvantages: restricted to ejaculates with high sperm count and motility, low yield, spermatozoa can be massively damaged by reactive oxygen species, significant decrease of the percentage of normally chromatin-condensed spermatozoa (Henkel & Schill, 2003). Furthermore, it is known to require a very delicate handling, and might be contaminated due to the procedure process. Incubator and centrifuge are needed. A significant drawback for such a procedure is the fact that it must be performed by a qualified fertility laboratory technician due to method complexity        Density gradient centrifugation: comprised of continuous or discontinuous gradients. The ejaculate is placed on top of the density media with higher density and is then centrifuged (for 15-30 minutes). Highly motile spermatozoa move actively in the direction of the sedimentation gradient and can therefore penetrate the boundary quicker than poorly motile or immotile cells, thus, highly motile sperm cells are enriched in the soft pellet at the bottom. Centrifugation is needed. Centrifugal pelleting of unselected sperm populations from human ejaculates causes the production of reactive oxygen species, that inducing irreversible damage to the spermatozoa and impairment of their fertilization ability (Mortimer, 1994), moreover dead and moribund spermatozoa and other cellular elements of semen (leukocytes, epithelial cells, anucleate cytoplasmic bodies, particulate debris, immature sperm cells and immotile sperm cells) can be found in the final pellet.        Costs: Relatively high costs per procedure (disposables, 2 gradients and medium).        Disadvantages: production of good interphase between the different media is a more time-consuming, potential risk of endotoxins contamination, Percoll® may no longer be used IVF/ICSI (Henkel & Schill, 2003). Centrifugation is required. furthermore, such a procedure is performed only by a qualified e fertility laboratory technician due to method complexity.        
Less frequently used techniques for sperm cells selection in laboratory include the following:                Migration-sedimentation: a swim-up technique combined with a sedimentation step. Spermatozoa swim up directly from liquefied semen into the supernatant medium and subsequently sediment in a cone. No centrifugation is needed. The procedure is conducted in a special chamber with a unique structure: a small tube creating a well within a larger tube. It is commercially produced: MSC1 (R1, U.K.).        Costs: Relatively high costs. In such a procedure the medium is also needed in the same volume of the semen sample which elevates the costs even more.        Disadvantages: since the motile sperm cells are isolated into said larger tube filled with sperm separation medium, the concentration of the same is diluted. Thus, the above mentioned method is restricted to ejaculates of high sperm count and good motility, has a very low recovery rate, special glass or plastic tubes are required, tubes are more expensive and relatively sensitive, for repeated use in IVF glass and plastic tubes must be sterilized (Henkel & Schill, 2003). More than 1 chamber is required for a 3 ml semen sample.        
Examples of systems whilst using the Migration-sedimentation technique:
ZSC-II: Conducted in a unique geometric configuration of the columns, which includes the conical cavity inside the ZSC. Combines the “swim-up/swim-down” phenomenon. Washes the sperm cells. Yielding a high-quality, morphologically normal, motile spermatozoa (according to manufacturer).Disadvantages of the ZSC-II: High costs per procedure, lab top incubator (dry bath) is needed (for 45-60 min), suitable for 2 ml semen sample only (medium is needed in the same volume of the semen sample).Multi-ZSC: combines the “swim-up/swim-down” phenomenon. Washes and simultaneously selects sub-populations of spermatozoa, no dilution and centrifugation. Yielding a high-quality, morphologically normal, physiologically superior motile spermatozoa (according to manufacturer). Dry bath or incubator are needed (again as before, the medium is needed in the same volume of the semen sample).
Disadvantages of the Multi-ZSC: Very high costs (approx.100$ per procedure).
Glass wool filtration: motile spermatozoa are separated from immotile sperm cells by means of densely packed glass wool fibres. The principle of this sperm separation technique lies in both the self-propelled movement of the spermatozoa and the filtration effect of the glass wool. A centrifugation step will be necessary to remove the seminal plasma (Henkel & Schill, 2003).Disadvantages of the Glass wool filtration: more expensive (than swim up technique), the filtrate is not as clean as it is with other sperm separation methods, remnants of debris are still present (Henkel & Schill, 2003). Self prepared (Van den Bergh et al., 1997), or marketed (SpermFertil® columns from Mello Holzhausen, Germany).Sephadex columns: sperm separation by means of Sephadex beads. (SpermPrep: ZDL Inc., Lexington, Ky., US). Pre-wash of the semen is needed (generation of free radicals). An improved column (SpermPrep II) allows semen filtration after dilution 1:1 with culture medium. Price: Relatively high costs per procedure (for the disposables including the beads only. Medium is needed in the same volume of the semen sample
Disadvantages of the Sephadex columns: High cost per procedure
Thus the above described methods require laboratory skills and equipment, frequently use external mechanical handling, or produce low yields of motile sperm cells.
Those traditional laboratory techniques require a designated laboratory, using a microscope and other laboratory equipment.
The main drawbacks are as follows:                Accessibility: Male fertility laboratories are not as accessible to patient as the treating doctor—longer time to result & treatment        Availability: No real time results        Cost: Semen analysis in a laboratory costs 150$-400$. Relatively high.        
Therefore there is a long felt need for rapid results, faster diagnostic benefits, better patient care by improving the time to treatment (TAT) in a point-of-care (POC) near-patient, for example in a doctor's clinic, and as a result decrease frustration, anxiety and uncertainty. Furthermore, Male fertility diagnostics and treatment is an underserved market. Semen assessment and sperm preparation are done in male fertility laboratories. Patients travel from Obstetrics and gynecology (OB/GYN) clinic to these facilities and back for each procedure. This time delay and logistics needed reduce treatment results. OB/GYN doctors must be available to deliver fertility treatments and ART as soon as patients return from fertility laboratories. OB/GYN doctors located far from fertility laboratories face a real accessibility challenge on their way to perform the IUI procedure.
Therefore, it is a long and unmet need to provide a sperm separation/preparation system and technique, intended to separate motile sperm cells in a semen sample, which overcome the above described drawbacks.
Furthermore, there is an unmet need to provide a sperm separation/preparation system which is simple to operate, requires no preliminary training and can be performed by doctors and healthcare professionals.
Such a system should be adapted for use in the doctor's office, clinics, laboratories and even home use.
Furthermore there is an unmet need to provide a sperm separation system which is based upon a natural separation procedure (i.e., no external interference, e.g., centrifuge, is operated to separate said sperm sample), resulting in high yield of sperm cells with desired characteristics for usage in fertility treatments.
Furthermore there is an unmet need to provide a sperm separation system which provides an enriched semen sample with high concentration of progressively motile sperm cells.